If the Cascadia Subduction Zone were to let loose, some predict from geological investigation that this fault line is capable of producing Mega Quakes of a 9.0 magnitude and producing a 100' tsunami wave. I have been trying to locate information on how far up the Columbia River a tsunami wave of 100' would travel inland and backup the rivers which feed into it.

This was one of leading factors for me 5 yrs. ago to seek employment outside of the big city (Portland). Along with having a dislike for large populated areas and knowing just how long it does take to get home on a Friday afternoon commute did not settle well for me if a natural disaster of any sort were to take place here.

It is what it is, there is no place on this earth that isn't in danger of some type of natural disaster, pick your flavor. At least there isn't any nuclear power plants here other than the ones at Universities used for education.

Which says, in essence, that Berkland's forecasts are no better than chance. It is an intriguing theory, all the same. Others might do the analysis differently, of course.

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Quake prediction will always be theory. If you go into the video understanding that his comments are only a set of theories.. then you're doing fine. Weigh the information for yourself.. do your own conditional thinking on the topic.. make your choices. That's all you can do.

The first of the earthquake zones is the Cascadia Subduction zone, which is located just off the coast of Washington and Oregon. This subduction zone can produce earthquakes as bis as any in the world. The fault spans over a thousand miles, meaning that it could produce up to a 9.0 magnitude earthquake!

The Juan de Fuca plate is being pushed by the Juan de Fuca spreading ridge. This spreading ridge, which is located hundreds of kilometers off the coast of Washintong and Oregon, is an area where new sea floor is being created. The Juan de Fuca plate then gets pushed under, or subducts, the North American plate, which is what we live on. As the Juan de Fuca plate tries to subduct, the plates are locked together by friction, causing the North American plate to bow upwards (top figure). When the tension becomes too great, the North American plate finally releases the tension and an earthquake occurs (lower figure). Work is currently being done by Washington's state seismologist to measure the amount of uplift that is occurring by using very accurate GPS (Global Positioning System) coordinates. The hope is that we can measure how much tension is building up on the Subduction zone so that one day we can tell when an earthquake is likely to occur.

The last time an earthquake was created by this fault was in 1700. With geologic evidence, as well as written records from Japan (which got hit by tsunamis created by the earthquake), we can deduce that it was a rather large earthquake that happened January 26, 1700. This earthquake was much larger than the Nisqually earthquake, possibly reaching up to a magnitude 9.0 on the Richter scale.​